\begin{table}[htbp]
\centering
\begin{tabular}{ c c c c c c c} 
  
 Polynomial Order & Mesh: & 2x2x2 & 4x4x4 & 8x8x8 & 16x16x16 & Overall Order of Accuracy \\ 
 \hline 
 \multirow{2}{*}{$p = 1$} & $L_2$ error & 5.76e-01 & 1.35e-01 & 3.22e-02 & 7.90e-03 &   \\ 
  
   & $\mathcal{O}(L_2)$ &   & 2.10 & 2.06 & 2.03 & 2.06 \\ 
 \hline 
 \multirow{2}{*}{$p = 2$} & $L_2$ error & 4.09e-01 & 5.52e-02 & 6.87e-03 & 8.53e-04 &   \\ 
  
   & $\mathcal{O}(L_2)$ &   & 2.89 & 3.01 & 3.01 & 2.97 \\ 
 \hline 
 \multirow{2}{*}{$p = 3$} & $L_2$ error & 9.77e-02 & 5.97e-03 & 3.78e-04 &   &   \\ 
  
   & $\mathcal{O}(L_2)$ &   & 4.03 & 3.98 &   & 4.01 \\ 
 \hline 
 \multirow{2}{*}{$p = 4$} & $L_2$ error & 1.12e-02 & 6.39e-04 & 2.07e-05 &   &   \\ 
  
   & $\mathcal{O}(L_2)$ &   & 4.13 & 4.95 &   & 4.54 \\ 
 \hline 
 \multirow{2}{*}{$p = 5$} & $L_2$ error & 1.53e-01 & 5.08e-03 & 6.92e-05 &   &   \\ 
  
   & $\mathcal{O}(L_2)$ &   & 4.91 & 6.20 &   & 5.55 \\ 
 \hline 
 \end{tabular}
\caption{Accuracy of HiFiLES for NS equations with source term in tetrahedral meshes at $t = 10$. $L_2$ error is the $L_2$-norm of the error in the energy field: $\rho e$}
\label{table:tetsError1} 
 \end{table}
